Depends where she lives. Autozone blew me off in San Diego, Autozone is not going to fix her car anyway, just sell her parts. Who's going to install the parts?
No one here can tell you why your light's coming on without hooking your car up to a machine. You're going to need a shop local to you to do that. Car's cost money, I hope it's not too much. it is probably a cheap pcv Smart of you to try and find the problem now instead of later.